Background: \ud Severe childhood and adolescent obesity (BMI>3.5SD) remains a significant public health priority with an increasing incidence [1] and is associated with significant morbidity including immediate and long-term cardiovascular, metabolic and psychological consequences [2]. Current non-invasive treatments including lifestyle modification and pharmaceutical intervention are of limited effectiveness in this population, which leaves permanent bariatric surgery as the only viable option. As an alternative, intra-gastric balloons offer a reversible, potentially safer and less invasive option for severely obese adolescents for whom all other available treatments have been exhausted.\ud \ud Methods/design: - \ud BOB is a non-randomised pilot study. A cohort of 12 obese adolescents (BMI > 3.5SD, puberty stage 4 or more) aged 13 - 16 years, will be recruited to the study, where an intragastric balloon (ORBERA – inflated to 500-700ml) will be inserted into the stomach for 6 months, whilst receiving intense, weekly, behavioural support for the family. Follow-up will continue for 18 months after balloon removal with reduced behavioural support. The primary outcome measure will be the change in body weight and BMI standard deviation score from baseline following six months with the intragastric balloon and lifestyle therapy. Secondary outcome measures include the assessment of weight maintenance at 18 months post balloon removal, biomedical outcomes including blood glucose levels, physical activity and physical fitness, and psychosocial outcomes such as paediatric health-related quality of life.
